BFR Developments

[Yazata]

Sudden Big Developments!! Preparing For Flight Today

If you like seeing two spaceships on the pad, this may be your last chance for a while.

The FAA relented and yesterday they granted approval for the Sn9 flight.

https://twitter.com/nextspaceflight/stat...9501142017

Today Boca Chica has received its evacuation notice. Residents were told flight early this afternoon.

https://twitter.com/BocaChicaGal/status/...6027269120

Elon's private jet just arrived.

https://twitter.com/ElonJet/status/1356497349246353410

The FAA is informing air traffic control of a launch today. (Towards the bottom under 'route constraints'.)

https://www.fly.faa.gov/adv/adv_otherdis...e=02/02/21

Wind (6 knots) and weather are good.

They are preparing to move the giant crane back to the launch area prior to the launch.

Photographers across the road from the pad are being told that they have to leave.

Lab Padre's Pad Cam. Lab has six different streams from different cameras from different angles. You can switch between them on the youtube page. Check'em out!

https://www.youtube-nocookie.com/embed/Z72Au8Px7mM

Live stream by nsf

https://www.youtube-nocookie.com/embed/wfHqbahPKpY

Tim Dodd will be streaming here (stream hasn't started yet)

https://www.youtube.com/channel/UC6uKrU_...HMTY3LIx5Q

Felix is streaming from Germany here. (He uses Lab's video with permission, with his own commentary.)

https://www.youtube-nocookie.com/embed/1LUEQmsnVac

[Yazata]

Tim's stream is live

https://www.youtube-nocookie.com/embed/l4-PwxnJimg

Lab's nerdle cam (a nerdle is a herd of nerds)

https://www.youtube-nocookie.com/embed/Ky5l9ZxsG9M

SpaceX's stream will start shortly before t -0 here

https://www.spacex.com/vehicles/starship/

[Yazata]

And big personnel moves at SpaceX that may or may not be related to the FAA difficulties.

Hans Koenigsmann, the fourth person hired at SpaceX back at its beginning back in 2002 is retiring. He says that he will continue on at SpaceX part-time. Hans has been a top figure at SpaceX, up there with Gwynne immediately below Elon.

And he is going to be replaced as SpaceX Vice President for Build and Reliability by Bill Gerstenmeier. "Gerst" (his nickname) was previously head of human spaceflight at NASA, and in charge of the International Space Station program before that. He's a certifiably big name in aerospace. He left NASA last February and became a "consultant" at SpaceX. There are federal laws preventing top federal people from going to work with government contractors that they awarded contracts to for a year after they quit government service. And that year's lockout ends this month. 

There's some speculation that SpaceX might have had to throw the FAA a bone and Gerst is that bone. (Put the grownups in charge. And there's nobody in the industry more respected than Gerstenmeier.) But the timing of the whole thing does suggest that it was in the works for some time.

[Yazata]

There seems to have been a short hold because of range violators. Sheriffs drove out and chased off a silver pickup truck. Things seem to be back on track.

2:13 PM CST - Propellant loading underway. Speculation that launch will be very roughly 2:25 PM CST.

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Once again landing was the problem.

Word is initially that one of the Raptor engines failed after relight. Unclear what the precise problem was but Sn9 was feeding telemetry back until the end.

Sn10 seems to be ok.

[confused2]

I got the impression the SN8 vectored thrust did a lot more vectoring than SN9 and the SN9 control system lost the will to live in the final moments. I'm guessing the engines have different jobs and SN8 lost the thrust engine and SN9 lost the attitude correction engine. With both engines firing and no bits dropping off hopefully SN10 will nail it.

[Yazata]

The plan was for two engines to relight for landing. But video definitely shows that only one engine succeeded in doing that. Sn9 performed the pitch-up maneuver but seemingly couldn't halt that rotation which overshot, and the one engine couldn't bring Sn9 back to vertical or zero out the remaining descent velocity. So it hit the ground at about a 45 degree angle to the vertical. But it still managed to control its aerodynamic descent and find its way back from high up in the sky. It didn't crash off the site, on top of Sn10 or on the tank farm. It hit right where it was supposed to, on its lovely landing pad. Just not at the desired speed or attitude. My guess (pure speculation) is that an engine blew a turbopump.

https://twitter.com/NASASpaceflight/stat...9619142659

Chris Bergin points out that Falcon 9 is today one of the most reliable orbital boosters with a record of more than 50 successful landings. So many that they are starting to seem routine. But figuring out how to land them originally involved a whole series of fiery crashes. Chris expects Starship to figure it out even faster than Falcon given how close they came on the first two attempts.

The famous SpaceX Falcon blooper reel

https://www.youtube.com/watch?v=bvim4rsNHkQ

[Yazata]

Road is closed and they are doing more pressure testing on 7.2. Perhaps today is the day they press it to failure. Right now they seem to be cycling, pressing it, releasing the pressure, then pressing again, perhaps to higher and higher pressures each time.

It's on LabPadre's Pad Cam. Listen to this with the sound on. The thing is singing!!! I swear it's true.

Eeriest thing I've ever heard. It saw what happened to Eileen and it probably knows that it's doomed. So it's singing!

Edit: The sad mournful singing has stopped and it's just hissing now. I'm guessing that the singing was vibrations in the steel associated with the abrupt temperature change of flowing liquid nitrogen in.

Edit2: The filled it to the top with liquid nitrogen, closed off the pressure relief valves, and about four minutes later it suffered what looked like a small burst seam on the right side. Big vapor plume but little liquid released. They appear to be detanking now.

For a test-to-destruction, there was very little destruction. 7.2 can probably be repaired with a few welds. I'm not a rocket scientist, but my layman's intuition tells me that it looked like a good result. (Depending on what pressure they reached.) So maybe going to thinner steel isn't such a crazy idea.

Edit3: They appear to be refilling 7.2 with liquid nitrogen and repressing, despite the leaks (which are small). It isn't clear what's happening.

One of the people in the LabPadre chat remarked that this is like watching Mythbusters. So true! (And as Mythbusters taught us, duct tape can fix anything.)

https://www.youtube-nocookie.com/embed/Z72Au8Px7mM

[Yazata]

Elon tweets!

Elon posted this picture, saying "next time we try the *up* method"

[Image: EtXqUsjXIAIM_yS?format=jpg&name=small]

Somebody asked why, if they need two engines to land, they don't just light all three engines, choose the best two and shut the third engine down.

We have seen static fires that last less than a second, enough time to spool up the turbopumps, ignite the engine and get hundreds of milliseconds of engineering data, a long time to electronics. Enough time for a computer to compare three sets of engine data, decide which one looks worst, and shut that engine down. While three engines are too much thrust for landing, less than a second shouldn't hurt too bad. This way if one engine fails to light or blows a propellant pump on startup, you still have the neccessary two to complete the landing.

Elon "We were too dumb"

https://twitter.com/elonmusk/status/1357256507847561217

Elon "It was foolish if us not to start 3 engines & immediately shut down 1, as 2 are needed to land."

https://twitter.com/elonmusk/status/1357422126161145856

Somebody asked whether these changes will be included on the Sn10 test flight.

Elon: "Yes"

https://twitter.com/elonmusk/status/1357422799330107393

[Yazata]

Weekend news update.

Sn11 has received its nose in the High Bay. So it's nearing completion. It still needs its rear fins and all the final fitting-out stuff. And no leaning!

https://twitter.com/BocaChicaGal/status/...0711484417

Sn 10 sits alone on test stand A at the launch area, after Eileen leaned too hard and belly-flopped into the landing pad.

https://twitter.com/jdeshetler/status/13...0332244997

Crews have been collecting her scattered bits from all around. Here's her engines that let her down so inexcusably.

https://twitter.com/BocaChicaGal/status/...7104672771

Sn10 received three new Raptor engines over the weekend.

https://twitter.com/BocaChicaGal/status/...7021604868

Mary says that she has received the 'overpressure' warning notice for Monday, so a program of static fires is beginning.

Talk is that they are aiming towards flying Sn10 around the end of the month, God and FAA willing... (The difference between them is that God doesn't believe that he's the FAA.) Word is that McGregor has been re-examining the test-stand results from all the Raptors that they have on hand in hopes of delivering a good reliable set that won't flame out.

[Yazata]

Today (Tuesday) is a really big construction day at the Superheavy's Orbital Launch Complex. Dozens of concrete trucks one after another as foundations are poured. More deep piles being drilled (for the huge Superheavy pedestal stacking crane?) Hundreds of workers scurrying everywhere. Quite a sight to see.

And the workers know when they are being photographed too, and sometimes wave at the cameras or even pose for shots.

https://twitter.com/DaytonCostlow/status...5453783045